Due to the increasingly popular practice of playing computer video games over the Internet and other digital media, it would be advantageous to digitize the analog video output of the computer game console device before it is sent to its destination. The maximum resolution for the output signal of certain platforms, such as the Wii video game console manufactured and sold by Nintendo, is 720×486 pixels, running at 60 frames per second, progressive scan “extended definition” resolution (sometimes referred to as SMPTE293M, and referred herein as “480p60”), when transmitted over analog component video cables.
In interlaced scanning such as commonly used for television sets, a frame representing a picture is split into two separate fields. One field may include odd lines of the picture and the other field may include even lines of the picture. The two fields constitute a frame. A picture formed by interlaced scanning is drawn on the screen in two passes, first by scanning the horizontal lines in the first field, retracing to the top of the screen and then scanning (or interlacing) the horizontal lines in the second field in-between the first set of lines. Interlacing field 1 and field 2 at 60 fields per second yields an effective 30 frames per second frame rate.
In non-interlaced scanning, the picture is formed on the display by scanning all of the horizontal lines of the picture in one pass from the top to the bottom. This is sometimes also referred to as “progressive scanning”. Unlike interlaced scanning, progressive scanning involves complete frames including both odd and even lines, in other words, each scan displays an entire frame. For example, in progressive scanning, a frame rate of 60 frames per second causes 60 frames to be formed on the display, in contrast to interlaced scanning, where a field rate of 60 fields per second causes only 30 frames per second to form on the display. This is at least one reason why the progressive mode provides better quality pictures than the interlaced mode.
Currently, it would be desirable to digitally capture an analog 480p60 video signal, while maintaining the refreshing rate of 60 frames per second, as well as the progressive nature of scanning of the frames. Furthermore, the capture process in the past often involves the resizing of the 480p60 video picture into a 720p60 video picture. In other words, the resolution of the picture changes from 720×486 pixels, 60 frames per second, progressive scanning, to 1280×720 pixels, 60 frames per second, progressive scanning (referred herein as 720p60 or 720p space/frame). However, existing video scaler systems that convert 480p60 video to 720p60 video rescale the picture so that the resized picture is forced to fill the whole higher-resolution 720p frame. This results in scaling artifacts, because of the non-integer ratio between 480p resolution and 720p resolution, and the size mismatch between the 0.9 (CCIR 601) NTSC lower definition pixel and the 1.0 square HDTV pixel.
One exemplary illustrative non-limiting method and apparatus for efficient digital capture of an analog video signal output of a computer game console, while maintaining its 60 frames per second rate and the progressive scanning mode of the video includes the resizing of the 480p60 video picture into a pixel-for-pixel translated replica inside the 720p60 space. A video scaler device is used to convert the 720×486p video signal of the Wii output into a 1280×720 @ 59.94p signal. By reducing the number of active lines of horizontal resolution and active lines of vertical resolution inside the higher definition 1280×720 space, the output picture is made to reflect the same number of pixels as the original 480p60 image, thus avoiding any scaling artifacts that are normally produced by the scaling process.